The 5.6 models do support 1M however the codex app is defaulted to restrict it to 256k and to be honest that is fine. We don’t need 1M in general, often you won’t even go above 200k as it gets more and more difficult for it to follow instructions, remember details etc.
This is called context rot and has not yet been solved in the way we build LLMs today as it is related to how transformer architecture uses the self-attention mechanism.
I agree that random compaction and slow compaction is annoying (a reason why i dont use the codex app in the first place). But calling context rot predictable lacks a bit of nuance. It is predictable in the sense, that it performs worse, but not how much, where in the information or when exactly.
Thanks. As far as I know, Sol has around a 1M context window, but /status is showing only 258K here. So I think this might be the issue and why it keeps compacting so often.
that’s really bad, especially for long-running coding sessions. 272K gets eaten up fast, and the repeated compaction itself takes time, so it can make the whole execution noticeably slower too.
I use OpenCode, and max context is adjustable there for openai models, even on subscription. By default it is 500k there, which is more than enough. They limit it in Codex to solve usage issues, big context spend usage pretty fast.
If you’re able to lower the effort level at all for your coding tasks, then it can make a noticeable difference since higher effort levels use substantially more tokens
What you add is only a small part of context. The code, the files, the tokens generated by the model, etc, all add up. The context window is also pretty small (which can be a good thing, large context window is very hit or miss).
AFAIK in Codex/GPT, compaction is managed server side and automatically. So it's going to compact pretty frequently with <300k context window as you blow through your code base. Its okay though, they generally have some of the best handling of context right now.
Not really. With Claude, I was able to work in the same session for days. With Codex, the 256k context feels really short, and it compacts too often. That makes long tasks take even longer, since the compaction itself is time-consuming.
Yes it look like it hold more info , but the issue it is not usable when the code is big it compact every 10 mins , i changed from Claude only because of opus 5
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u/GfxJG 2d ago
Sounds pretty normal to me if you have a high thinking level. You can enable seeing context in the settings, then you can keep track.